Utility of Indigenously Developed Square Grid Method for Evaluation of Tumor-Stroma Ratio and Stromal Tumor-Infiltrating Lymphocytes in Invasive Breast Carcinoma: A Pilot Study

Background & Objective: Invasive breast carcinoma (IBC) is the most diagnosed cancer among women in India. The conventional visual method of evaluation of Tumor-Stroma Ratio (TSR) and Stromal Tumor-Infiltrating Lymphocytes (sTIL) appears to be subjective. The present study aims to evaluate the utility of the indigenously designed square grid method for the evaluation of tumor-stroma ratio and stromal tumor-infiltrating lymphocytes in invasive breast carcinoma by assessing the inter-observer variability.Methods: This was a retrospective study conducted at a rural tertiary care referral institute from July ۲۰۱۸ to June ۲۰۲۰. In each case, microphotographs were taken from ۱۰ representative fields in H&E-stained sections for evaluating TSR in low-power and sTIL in high-power. Both the parameters were evaluated employing an indigenously designed square grid applied onto microphotographs in the PowerPoint slides by making use of principles of the Pythagorean theorem. Both parameters were separately evaluated by two pathologists. Cohen kappa statistics was the statistical tool used to analyze inter-observer variability.Results: Thirty cases were analyzed. Invasive breast carcinoma of no special type (IBC-NST) was the most common histopathological type (۲۶ cases (۸۶.۶۷%)). For TRS evaluation, a Kappa value of ۰.۷۸ suggested substantial agreement with an agreement of ۹۱.۶۷%. For sTIL evaluation, a Kappa value of ۰.۵۱ suggested moderate agreement with an agreement of ۸۸.۳۳%. The P-values were statistically highly significant (P<۰.۰۰۱).Conclusion: The square grid method is a novel technique for evaluating TSR and sTIL in invasive breast carcinoma. It can be considered an example of the application of Pythagoras’ theorem in Pathology.

کلیدواژه ها:

Cancer ، Inter-observer variability ، pathology ، Technique